The present invention relates to acoustics and, more particularly, to an acoustic system for cancelling out-of-phase reflected soundwaves of audio output systems.
Phase is the position at a point in time (an instant) on a waveform cycle, for example a soundwave. A cycle is defined as the interval required for the waveform to return to its arbitrary initial value. Phase can also be an expression of relative displacement between two corresponding features (for example, peaks or zero crossings) of two waveforms having the same frequency, where the waveforms are identical and originated at identical positions (i.e., the same waveform) but where one of the waveforms is a reflection (off, say, a reflective surface) of the other.
The wall behind speakers tends to act as such a reflective surface, reflecting the original “direct” (zero delay) soundwave being outputted from the speakers so that when the reflected soundwaves reach the listener they are out of phase relative to the original “direct” outputted soundwaves. This dissonance results in inferior overall acoustics of the acoustic space and sound quality of the output.
Current sound quality solutions include acoustical devices such as diffusers or absorbers, but they do not address the out of phase reflections problems; rather their purposes are limited to diffusion and absorption of unwanted soundwaves, respectively.
As can be seen, there is a need for an acoustic system for selectively cancelling out-of-phase reflected soundwaves of audio output systems. The acoustic system being adapted to partially cancel the out of phase reflections from reflective surfaces adjacent to the audio output source. The present invention does not absorb or diffuse such back-wave reflections, rather it makes corrections to the back-wave reflections. When adjustably aligned with the acoustic center of the audio output devices (speakers) and partially covering the reflective surface adjacent to the audio output devices, the system embodied in the present invention cancels the out of phase reflections leaving the in-phase reflections that synchronize with the direct soundwaves, engendering a major improvement in stereo sound reproduction.